Illuminated fabric air duct

ABSTRACT

To provide a room with a soft lighting effect and to enhance the appearance of an exposed air duct, a fabric duct is provided with a light-transmitting fabric wall that is illuminated, such that light from inside the duct travels outward into the room. In some embodiments, various colored lights and/or blinking patterns create special lighting effects that simulate the temperature or flow rate of the air being conveyed through the duct. In some cases, ultraviolet light is used to help kill microorganisms inside the air duct.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The subject invention generally pertains to air ducts and more specifically to an illuminated fabric air duct.

[0003] 2. Description of Related Art

[0004] Many HVAC systems (heating ventilating and air conditioning systems) include a network of air ducts with several discharge registers that distribute forced air to various rooms or areas within a building. Conventional air ducts are made of sheet metal, which is functional, but often considered not very attractive. But their appearance is usually not that important, as ductwork is often conveniently installed where they are out of sight, such as hidden above a ceiling or below a floor of the area being ventilated.

[0005] However, some buildings, such as warehouses and factories, do not have a convenient, out of sight location to install metal ductwork. In such cases, the ductwork is often installed just below the ceiling where it is in clear view. Moreover, if the ductwork conveys cool air, condensation may form on the exterior metal walls of the ducts, which may then drip onto the inventory or personnel below. The consequences of the dripping can range anywhere from a minor irritation to a dangerously slippery floor for the personnel, or complete destruction of the products it may drip on (especially in food-processing facilities).

[0006] Sometimes, temperature differentials between the ducts and the air being conveyed creates condensation on the interior of the ducts. The presence of condensed moisture on the duct's interior may form mold or bacteria that the duct then passes onto the room or other areas being supplied with the conditioned air.

[0007] In some applications, the rooms or areas being served by the ductwork require a more even distribution of air than what can be achieved with several spaced-apart discharge registers. Metal ducts with localized discharge registers have been known to create uncomfortable drafts and unbalanced localized heating or cooling within the discharge registers. Metal ducts with localized discharge registers have been known to create uncomfortable drafts and unbalanced localized heating or cooling within the building. In many food-processing facilities, where the target temperature is 42 degrees Fahrenheit, a cold draft can be especially uncomfortable and possibly unhealthy.

[0008] Consequently, for the reasons just mentioned, air ducts made of fabric are often preferred over those made of sheet metal. Fabric ducts typically have a flexible fabric wall that is porous and/or includes additional holes along its length for evenly dispersing air from within the duct into the areas being conditioned or ventilated. The fabric's ability to “breathe” appears to minimize condensate accumulation on both the interior and exterior of the duct. An example of such a duct is a DUCTSOX by the Frommelt Safety Products Corporation of Milwaukee, Wis.

[0009] Since fabric ducts disperse air generally along its entire length, fabric ducts are usually installed such that they are fully exposed to the area they serve. Fabric ducts are often suspended from a horizontal cable or track mounted just below the ceiling of the building. Thus, they are usually clearly visible, which makes their appearance generally more important than if they were hidden. Although many prefer the appearance of fabric ducts over those made of sheet metal, there may always be a desire to further enhance their appearance.

SUMMARY OF THE INVENTION

[0010] A fabric air duct is provided with a light-transmitting fabric wall that is illuminated, such that light travels outward from inside the duct. Such a fabric duct may exhibit an enhanced appearance over existing ducts, and has added functionality.

[0011] In some embodiments, a fabric air duct and a light source are suspended underneath a ceiling using the same hangers.

[0012] In some embodiments, the light-transmitting fabric wall is translucent to broadly disperse light into a room.

[0013] In some embodiments, the interior of a fabric air duct is illuminated with ultraviolet radiation to kill or inhibit the growth of microorganisms, such as mold, fungus, or bacteria.

[0014] In some embodiments, the interior of a fabric air duct is illuminated with a light that changes with a changing condition of the air being conveyed through the duct, wherein the changing condition of the air is temperature, pressure or rate of airflow.

[0015] In some embodiments, the interior of a fabric air duct is illuminated with blinking lights to create a twinkling or moving-light effect.

[0016] Alternatively, light may not pass through the duct, but the duct and indirect lighting may be commonly mounted.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 is a front view of one embodiment of an illuminated fabric air duct.

[0018]FIG. 2 is a cross-sectional end view taken along line 2-2 of FIG. 1.

[0019]FIG. 3 is similar to FIG. 2, but with the air duct inflated.

[0020]FIG. 4 is a cross-sectional end view of an inflated cylindrical fabric air duct illuminated by an adjacent light source.

[0021]FIG. 5 is a front view of another embodiment of an illuminated fabric air duct.

[0022]FIG. 6 is a front view with a partial cut-away of another embodiment of an illuminated fabric air duct.

[0023]FIG. 7 is similar to FIG. 2 but with a light fixture directing light generally away from a fabric duct to provide indirect lighting to areas below the duct.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0024] To disperse light as well as air into a room, an air duct assembly 10, of FIGS. 1-3, includes a light source 12 shining through a light-transmitting fabric wall 14 of a fabric air duct 16. The term, “fabric,” refers to any pliable sheet of material that may or may not be air permeable or porous. Examples of a fabric include, but are not limited to, woven or knit cloth, flexible plastic sheeting that is not necessarily woven, plastic impregnated cloth, fiber reinforced plastic, and various combinations thereof. The term, “light-transmitting” refers to a material having the ability to pass light either through itself or through openings in the material, wherein the material may be transparent (colorless or tinted), translucent, or opaque with openings. Air duct 16 is shown with several hangers 18 suspending duct 16 from girder beams of a ceiling 20.

[0025] To provide duct 16 with the ability to convey air 22 along its length, longitudinal edges of fabric wall 14 connect to a top plate 24 to create a tubular shape, as shown in FIGS. 2 and 3. The tubular shape can be created by a variety of structures; however, in this example two channels 26 attached along the length of plate 24 couple opposite edges of plate 24 to two elongated beads 30 running lengthwise along fabric wall 14. A lengthwise sliding fit between beads 30 and channels 26 allows fabric wall 14 to be periodically removed for cleaning and later reinstalled. An air handler 32, such as a blower 34 disposed within a housing 36 or some other source of forced air, discharges air 22 through an interior 38 of duct 16. A fabric end cap 40 restricts or entirely closes off a downstream end of duct 16 to help develop a positive air pressure that inflates duct 16 when blower 34 is running, as shown in FIG. 3. When blower 34 turns off, duct 16 deflates, as shown in FIG. 2.

[0026] To expel pressurize air 22 from within duct 16 and disperse it into an exterior area 42 surrounding duct 16, fabric wall 14 is air-permeable. Air-permeability of wall 14 can be provided by fabric porosity and/or by small openings distributed along the length of duct 16.

[0027] To transmit light 44 outward from within duct 16 and disperse the light into area 42, light source 12 is mounted to project an appreciable amount of its light 44 into duct 16. In this embodiment, light source 12 projects its light 44 through plate 24, which illuminates an interior surface 46 of duct 16. Plate 24 can be made of clear plastic or glass, or plate 24 could be translucent or even opaque with a central opening for the light. From the illuminated interior 38, light 44 travels outward from duct 16 after passing through the light-transmitting fabric wall 14. Light source 12 is schematically illustrated to encompass anything that can provide illumination. Examples of light source 12 include, but are not limited to, a fluorescent light, an incandescent light, halogen bulb, an ultraviolet light, and a lens or reflective surface that redirects light from another light source.

[0028] Light source 12 can be selectively turned on and off as needed. In some cases it may be desirable to have light source 12 turn on and off automatically with the operation of blower 34. For example, light source 12 turns off when blower 34 turns off, and turns on when blower 34 turns on, as shown in FIGS. 2 and 3, respectively. Conversely, light 12 turning on when blower 34 turns off may be useful when light source 12 is an ultraviolet light used for killing microorganisms that tend to grow in dark, stagnant environments. A combination of the two approaches could also be useful. For example, a conventional fluorescent light could be turned on and off as needed, and an additional ultraviolet light could be operated whenever blower 34 turns off.

[0029] In another embodiment, shown in FIG. 4, an air duct 48 having a generally cylindrical, light-transmitting fabric wall 50 is situated adjacent a light source 52. This tends to provide duct 48 with a “glowing” effect when most or at least 20 percent of the light emitted from light source 52 reaches duct 48. In other words, angle 54 is at least 20 percent of the sum of angles 54, 56 and 58. The glowing effect is achieved by light 60 first passing through fabric wall 50 to illuminate an interior 62 of duct 48 and then passing through fabric wall 50 again to shine outward, away from duct 48.

[0030] Air duct 48 can also be illuminated as shown in FIG. 5. Here, two light sources 64 and 66, in the form of a conventional spot light or a flood light, shine in a direction generally parallel to the duct's length or generally parallel to the direction that air 22 flows through duct 48. This illuminates the interior of duct 48 and thus illuminates its exterior, as well. Light 66 disposed outside of duct 48 illuminates the duct's interior by projecting its light 68 through an airflow opening 70 or closed window of an end cap 72. Light 66 is disposed within the interior of housing 36 and/or the interior of duct 48. Either light 64 or 66 can be used alone or with each other.

[0031] In some cases, it may be desirable to have one light 64 or 66 emit red light and the other blue. The red one could be turned on when duct 48 is conveying warm air, and the blue one could turn on when duct 48 is conveying cool air. The distinction between the red and blue colors may be more apparent if the fabric of duct 48 is white or nearly white.

[0032] Several openings 74 in duct 48 provide discharge airflow rates that are higher than what may be achieved by relying on fabric porosity alone. Openings 74 not only allow the use of nonporous fabric, but openings 74 also allow an opaque fabric wall to transmit light.

[0033] Other special lighting effects can be achieved with a duct assembly 76 of FIG. 6. In this embodiment, a string of lights 78, such as those often referred to as “rope lights,” “Christmas lights” or “holiday lights,” serves as the light source that illuminates the interior, and thus the exterior, of a light-transmitting fabric air duct 80. The string of lights 78 includes a series of small bulbs 82 that can blink on and off randomly to provide a “twinkling” effect or can blink in a sequential pattern to provide a “traveling light” effect where the lights appear to be moving. If blower 34 is a dual-speed blower, lights 82 can be blinked in such a way as to create a perceived speed of movement that increases with an increase in blower speed. Light bulbs 82 can be of an assortment of different colors or be all of the same color. Lights 82 do not necessarily have to blink, but instead can be left on or off continuously, as needed.

[0034] In another embodiment, an air duct assembly 10′ is similar to that of FIGS. 1-3; however, instead of light source 12 focusing most of its light toward duct 16, duct assembly 10′ includes a light source 12′ that is inverted to direct most of its light 44′ away from duct 16. This provides indirect lighting to areas underneath duct 16 as the light reflects off the ceiling and other surfaces. Yet, air duct assemblies 10 and 10′ are similar in that each includes hangers 18 that suspend both a light source and a fabric air duct from underneath a ceiling.

[0035] Although the invention is described with reference to a preferred embodiment, it should be appreciated by those skilled in the art that various modifications are well within the scope of the invention. Therefore, the scope of the invention is to be determined by reference to the claims that follow. 

I claim:
 1. An air duct assembly adapted to convey forced air, comprising: a light source; and a fabric air duct coupled to the light source and being adapted to convey the forced air through an interior of the fabric air duct.
 2. The air duct assembly of claim 1, further comprising a hanger adapted to suspend both the fabric air duct and the light source.
 3. The air duct assembly of claim 1, wherein the light source shines away from the fabric air duct to provide indirect lighting underneath the fabric air duct.
 4. The air duct assembly of claim 1, wherein the fabric air duct is translucent.
 5. The air duct assembly of claim 1, wherein the fabric air duct is air-permeable.
 6. The air duct assembly of claim 1, wherein the fabric air duct is inflatable.
 7. The air duct assembly of claim 6, wherein the fabric air duct changes from being inflated to deflated, with the fabric air duct being more illuminated when inflated than when deflated state.
 8. The air duct assembly of claim 1, wherein the light source is disposed within the interior of the fabric air duct.
 9. The air duct assembly of claim 1, wherein the light source includes a fluorescent bulb that illuminates the interior.
 10. The air duct assembly of claim 1, wherein the interior is illuminated by ultraviolet light.
 11. The air duct assembly of claim 1, wherein the light source includes a plurality of discrete light sources disposed within the interior of the fabric air duct.
 12. The air duct assembly of claim 11, wherein the plurality of discrete light sources includes lights of different colors.
 13. The air duct assembly of claim 11, wherein the plurality of discrete light sources blink on and off.
 14. The air duct assembly of claim 13, wherein the plurality of discrete light sources blink on and off to create a traveling-light effect.
 15. The air duct assembly of claim 13, wherein the plurality of discrete light sources blink on and off at a blinking rate that increases with an increase in a rate of airflow of forced air through the fabric air duct.
 16. The air duct assembly of claim 1, wherein the fabric air duct is adapted to selectively convey warm air and cool air with the light source projecting at least one color of light when the fabric air duct conveys the warm air and with the light source projecting at least another color of light when the fabric air duct conveys the cool air.
 17. The air duct assembly of claim 1, wherein the light source is disposed outside the interior of the fabric air duct yet illuminates the interior.
 18. The air duct assembly of claim 1, wherein the light source illuminates the interior by projecting light substantially parallel to a direction along which the forced air travels through the fabric air duct.
 19. An air duct assembly adapted to convey force air and being mountable underneath a ceiling, comprising: an inflatable fabric air duct; a light source; and a hanger coupled to the inflatable fabric air duct and the light source, wherein the hanger is adapted to suspend both the inflatable fabric air duct and the light source underneath the ceiling.
 20. The air duct assembly of claim 19, wherein the light source projects most of its light away from the inflatable fabric air duct to provide indirect lighting underneath the inflatable fabric air duct.
 21. The air duct assembly of claim 19, wherein the light source projects most of its light at the inflatable fabric air duct.
 22. The air duct assembly of claim 19, wherein the inflatable fabric air duct is translucent.
 23. The air duct assembly of claim 19, wherein the inflatable fabric air duct includes an air-permeable fabric wall.
 24. The air duct assembly of claim 19, wherein the light source is disposed inside the inflatable fabric air duct.
 25. The air duct assembly of claim 19, wherein the light source includes a fluorescent bulb.
 26. The air duct assembly of claim 19, wherein the light source projects ultraviolet light.
 27. The air duct assembly of claim 19, further comprising a plurality of light sources disposed inside the inflatable fabric air duct.
 28. The air duct assembly of claim 27, wherein the plurality of light sources includes lights of different colors.
 29. The air duct assembly of claim 27, wherein the plurality of light sources blink on and off.
 30. The air duct assembly of claim 27, wherein the plurality of light sources blink on and off to create a traveling-light effect.
 31. The air duct assembly of claim 19, wherein the light source directs light substantially parallel to a direction along which forced air travels through the inflatable fabric air duct.
 32. A method of mounting a fabric air duct and a light source, comprising: suspending the fabric air duct from an elongated hanger; and suspending the light source from the same elongated hanger.
 33. The method of claim 32, further comprising projecting light from the light source such that most of the light is directed away from the fabric air duct.
 34. The method of claim 32, further comprising projecting light from the light source such that most of the light is directed toward the fabric air duct. 